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Quantitative answer on seated vs. standing power(10 posts)

Quantitative answer on seated vs. standing powerPODIUMBOUNDdotCA
Oct 7, 2002 11:08 PM
After asking this question a few days ago I am now looking for *quantitative* information that standing produces more power than seated.

Thanks,
Nick
PodiumBound.ca
re: Quantitative answer on seated vs. standing powerInhighgear
Oct 8, 2002 3:06 AM
Quanitative...OK...Count how may sprinters are standing on the pedals vs how many are sitting coming up on the last 50 yards of any race.
Not quantitative, but hopefully reasonable...fbg111
Oct 8, 2002 3:23 AM
Imho, I think that people stand so they apply not only their leg strength, but also their body weight to the pedals. They increase the overall force applied to the pedal by taking more advantage of gravity. According to what I've learned, correct weight distribution sitting consists of about equal distribution between feet on pedals, butt on saddle, and hands on bars. When you lift off the saddle, your distribution changes to ~50/50 pedals/bars, or maybe more so on the pedals. When standing, many riders rock the bike (and their body somewhat) back and forth in order to apply all their body weight to one pedal at a time. Doing this helps push the pedal down harder (muscle + gravity instead of just muscle). Taking your butt off the seat has to transfer that downward force somewhere, and I think riders naturally transfer as much as they can handle to their downward stroke on the pedals.

One thing I wonder is, do good riders still pull up the opposite pedal using their hamstring muscles while standing? I think they do this sitting, but standing too? Or do they just relax those muscles and focus purely on the downstroke for all their power?
..but if you were applying your body weight..Spunout
Oct 8, 2002 4:01 AM
What is additionally applied to the pedals is the force previously used to support your a$$ as it is no longer on the seat.

I think standing offers a stretch, use some different muscles, let your 'spinning' muscles recover.

IMHO: STanding=quads, sitting=hamstrings. Opinions welcome please.

True, sprinters are always 'almost' seated, but I notice at 120-150rpm it is best to 'hover' over the nose of the saddle.
I agree you use...Wayne
Oct 8, 2002 4:18 AM
muscles differently when sitting vs. standing but it's the same muscles. The primary muscles that apply force to the cranks are the quads and glutes (knee and hip extensors respectively). Calves, hamstrings, low back muscles primary serve stabilization/coordination functions. I don't doubt that the hamstrings may be required more in sitting vs. standing but still their role as far as getting power to the crank is minimal. I'm pretty sure that it has been demonstrated that you can't "pull-back" with the hamstrings or "pull-up" with the hip flexors sufficiently to contribute to the force at the cranks as long as the extensors on the opposite leg are pushing down on the crank (i.e normal pedaling).
I don't know...fbg111
Oct 8, 2002 6:50 AM
When I switched from mashing to spinning a few weeks ago I know I started using my hamstrings and hip flexors to pull the pedal up much more. I know I can't spin very fast at all unless I do that, or unless I stand and sprint. I think a significant amount of power can come from that movement. Not more than pushing down, but enough to make a difference.

Also, hip flexors and hams are some of the strongest parts of a runner's body, as fast running requires pulling your upper leg up very high using those muscles. After using glutes and hams to push off, I'd bet that's the next most strenous muscle use in running. It could be that way with biking too.
Here's how to measure:cyclequip
Oct 8, 2002 3:56 AM
When seated, leg power is limited by a rider's seated mass and the frictional resistance of the saddle, plus the rider's ability to pull himself FORWARD using the bars. When standing a rider has the full benefit of his mass plus his ability to use the bars to pull himself DOWNWARDS.
So go to your bathroom and get a bathroom scale and weigh yourself. Now make sure your basin is firmly anchored - put the scale in front of the basin and stand with one foot on the scale and one foot touching the floor (shared mass) - take the reading. Now grip the basin and pull yourself down as hard as you can onto the scale. Take the reading. You tell me which is the highest reading you get.
power v. torqueDougSloan
Oct 8, 2002 7:01 AM
Torque accellerates the bike. You generally get more torque standing. Power determines top end. You get more power at high rpms, and high rpms are difficult standing. I've tested this theory on trainers with watt meters, and it is undoubtedly true (observation of sprinters confirms this, too).

Doug
check the research journalsBryanJL
Oct 8, 2002 8:08 AM
That's going to be about the only way to get the kind of quant data you're looking for.

University libraries are the best bet. Two that came up in a search I did are:

Journal-of-applied-biomechanics
Medicine-and-science-in-sports-and-exercise

I expect the research will indicate that standing produces certain advantages in the begining of the sprint, which decay with time depending on the conditioning of the cyclist, length of sprint, and grade (wind too).

But, the journals are where ya need to look.

Bryan
check the research journals- second this stronglypeloton
Oct 9, 2002 1:21 AM
Getting to the nearest college library is the best place to find empirical, quantitative information. Check the research journals, and the electronic indexes. Try the Medline and SPORTDiscus for some more ideas. If they have a kinesiology department, you may be able to find a prof with some free time willing to talk as well.

Mostly what you will get elsewhere will be ancedotal and theoretical.